A row-crop harvester set up simultaneously to harvest several rows of crop such as corn, sunflowers, or the like has a plurality of forwardly opening throats each adapted to receive a respective row of the crop. Extending backwardly along each of these throats is a stretch of a conveyor chain such as described in the commonly owned jointly filed application Ser. No. 913,233, whose entire disclosure is herewith incorporated.
Each of these chains is spanned over an idler sprocket and a drive sprocket, the latter normally being positioned at the rear or downstream end of the respective throat. A chopper has its intake at these downstream ends at an intake station. Each of the conveyors therefore conducts stalk-type crop which has been cut at approximately ground level back to the transfer location where it is taken in and chopped. The chopped crop can thereafter be blown directly into a following trailer or an alongside separate vehicle, or can be temporarily stored.
The drive sprockets at the rear ends of the chains normally are carried on upright shafts having at their lower ends bevel gears meshing with respective bevel gears carried on a horizontal shaft extending transverse to the direction of displacement of the machine. Play between each driven bevel gear and each drive bevel gear is compensated for by vertically displacing the driven gears.
In order to reduce the width of the device at the rear transfer station it is known to have some of the drive shafts shorter than others so that some of the bevel gears will lie in a plane above the others. Such an arrangement adds considerable height to the machine at this location and greatly complicates the drive system.
It is also known to reduce the overall width of the conveyor arrangement at the downstream end by providing the drive sprockets for the central chains somewhat forwardly of the drive sprockets for the side or outer chains. This requires, however, a second horizontal transverse drive shaft so that, although the overall width of the system at the transfer station is reduced, the construction costs are elevated considerably.
Thus all of the known systems have the considerable disadvantage that they are relatively complex and, therefore, quite expensive. Furthermore adjustment of any of the known systems is a relatively complex matter, as is the replacement of any of the drive sprockets or drive subassemblies for the drive unit.